Trimming devices



Nov. 4, 1969 K. o. ADAMS 3,476,003

TRIMMING DEVICES 2 Sheets-Sheet 1 Filed June 5. 1967 INVENTOR. Kenn/h 0. Adams BY WITNESS W ogi p l Q 6w ATTORNEY Nov. 4, 1969 K. D. ADAMS TRIMMI'NG DEVICES 2 sheets sheet 2 Filed June 5. 1967 INVENTOR. Kenneth 0. Adams United States Patent 3,476,003 TRIMMIN G DEVICES Kenneth D. Adams, Long Valley, N.J., assignor to The Singer Company, New York, N.Y., a corporation of New Jersey Filed June 5, 1967, Ser. No. 643,725 Int. Cl. B2611 5/38 U.S. Cl. 83-357 8 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a trimming device. More particularly, this disclosure relates to a trimming device for cutting a continuous tape at the leading edge and the trailing edge of pieces individually connected to the tape in spaced relationship to each other.

BACKGROUND OF THE INVENTION In the prior art various trimming devices, whether actuated manually or automatically were used chiefly to cut or sever a piece in a single cutting operation. Of course the single operation could be done repeatedly but the operations remained unrelated to each other. Accordingly the only Way more than one edge of a piece could be trimmed was manually, which proved to be both costly and time consuming.

SUMMARY OF THE INVENTION In accordance with the present invention a novel trimming device is provided for cutting a continuous tape at the leading edge and the trailing edge of pieces individually connected to the tape in spaced relationship to each other. The trimming device comprises means for moving pieces connected to the tape at a predetermined rate of speed along a prescribed line of feed, means adjacent to the line of feed to sense the leading edge and the trailing edge of successive pieces and means adjacent the line of feed forwardly of the sensing means by a preselected amount to cut separately the leading edge and the trailing edge of successive pieces in a timed sequence actuated in response to the sensing means.

It is therefore an object of the present invention to provide an improved trimming device which avoids the prior art disadvantages; which is simple, economical and reliable; which feeds the taped pieces to the sensing and cutting means at a predetermined rate of speed; which feeds the taped pieces to the sewing and cutting means at a constant rate of speed; which feeds the taped pieces intermittently to the sensing and cutting means at a constant rate of speed; which uses a switch actuated, intermittently operated constant speed electric motor to drive the feeding means; which uses the tension of the reservoir of stored taped pieces available for feeding to counter-balance the weighted guide assembly which activates or deactivates said switch; which senses and cuts the leading edge and the trailing edge of successive pieces in a timed sequence; which uses a pneumatic sensor; which uses sensors that are selectively and adjustably positioned relative the cutting means; which uses a manifold of sensor tubes, only one of which will be operable at a time; which cuts the tape at the leading edge and the trailing edge of Patented Nov. 4, 1969 successive pieces by the interaction of the feeding, sensing and cutting means.

Other objects and advantages will be apparent from the following description of several embodiments of the invention and the novel features will be particularly pointed out in the claims hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS This invention is illustrated in the accompanying drawings in which:

FIGURE 1 is a diagrammatic perspective view of an apparatus embodying the present invention including means for feeding, sensing and cutting of a continuous tape at the leading edge and the trailing edge of pieces individually connected to the tape in spaced relationship to each other.

FIGURE 2 is a diagrammatic perspective view of another form of the sensing and cutting means of the present invention.

FIGURE 3 is a diagrammatic perspective view of still another form of the sensing and cutting means of the present invention.

DESCRIPTION OF THE INVENTION In the embodiment of the invention illustrated in FIG- URE 1 the novel trimming device, designated generally as 10, is shown including a feeding assembly 12, a sensing mechanism 14 that coacts with the feeding assembly 12 to actuate a cutting device 16 in a timed sequence.

FIGURE 1 shows a continuous tape 18 having a plurality of pieces 20 individually connected to the tape 18 in spaced relationship to each other being delivered to the feeding assembly 12. In the present specification the term tape shall mean any long and narrow strip of material which may be made of paper, metal, cloth, plastic, a chain of threaded stitches, or any other suitable connecting means. Also the method of joining the pieces to the tape are many and varied, but just as the material from which the tape is made is not intended to affect the scope of the present invention neither is the particular method of joining the pieces to the tape, with that illusrated being by means of threaded stitches.

In the present instance half pieces 20a are sewn together on a first sewing machine 22 and passed through guide means (not shown) that act to unfold the double layer to form a single piece that is fed to a second sewing machine 24. A continuous tape 18 from a suitably mounted roll 26 is fed underneath the piece 20 whereby the tape 18 and the piece 20 will be sewn together to pass to the feeding assembly 12 along a prescribed line of feed designated generally as 28. Sewing machines 22 and 24 in combination define a tandem heel seaming and undertaping unit that could be used for example in the making of canvas shoes. However, the crux of the present invention resides in the interaction of the feeding assembly 12, the sensing mechanism 14 and the cutting device 16 which provides for cutting the tape 18 at the leading edge and the trailing edge of successive pieces 20 and therefore is applicable to serve this purpose for any pieces connected to a continuous tape.

The feeding assembly 12, as well as the rest of the trimming device 10, will be connected to or mounted on a suitable frame (not shown). The feeding assembly 12 must be operated at a known or predetermined rate of speed so that the distance traveled along or parallel to the line of feed 28 from (1) a given sensing point to (2) a cutting point may be anticipated. The present embodiment uses a feeding assembly 12 that is intermittently operable at a constant rate of speed. a

The intermittent operation results from the cammin action of a finger 30 upon a normally closed electric switch 32 which is in circuit with an electric motor 34 which drives the feeding system at a constant rate of speed. Finger 30 is fixedly connected to a rod 36 journaled in bearings 38, which rod serves as a pivot member for the finger 30 and a pair of spaced bars 40 that each have one end thereof fixedly connected to the rod. A rod 42 is connected between the bars 40 at the other end thereof so that the bars will pivot in unison. Mounted on rod 42 is a spring loaded guide plate 44 held down by the tension of the tape 18 passing thereon. Plate 44 aids in delivering the pieces in an opened position to the feeding system. Other means (not shown) may serve to suitably support the pieces 20 prior to their passing onto the plate 44.

Cables 46 pass over pulleys 48 to dispose above the line of feed to have one end connected to weights 50 and the other end connected to the bars 40 intermediate the rods 36 and 42. The weights 50 urge the bars 40 to pivot in a counterclockwise direction as viewed in FIG- URE l which also acts to pivot the finger in a counterclockwise direction. However the movement of the bars responsive to the weights is opposed and ultimately counter-balanced by the tension exerted by the tape 18 upon bars 40 via rod 42. The resultant position of bars 40 and finger 30 depends upon the reservoir or stored amount of stitched pieces 20, or in other words, the length of the tape 18 between the sewing machine 24, and rod 42 and plate 44.

The continuous tape 18 at its forward end is held by the feeding assembly 12 via pieces 20 and is held at its rearward end adjacent the sewing machine 24. Relatively speaking this defines two fixed points between which the tape 18 engages the rod 42 and the plate 44 to exert a variable tension on the bars 40. When the reservoir of the tape 18 between these points is large the corresponding tension upon bars 40 will be slight, but on depletion of the supply the tension upon bars 40 will continuously increase. Accordingly, the lower position indicated by the full line representation of bars 40 shows a depleted supply of stitched pieces 20 resulting in the continuous tape 18 exerted increased tension bars 40 that causes fingers 30 to pivot in the clockwise direction as viewed in FIGURE 1 to open switch 32 and therefore break the circuit to stop the motor 34 of the feeding system. As the operator produced more stitched pieces the reservoir or stored amount of the continuous tape 18 increases, re-

sulting in a decrease in the tension exerted thereby, causing the bars 40 assuming the position indicated in phantom above the full line position. The turning movement represented by the phantom position of bar 40 would be sufiicient to release the switch 32 to its normally closed position and operate motor 34.

When the switch 32 is closed the electric motor 34 operates to drive a belt 52 and a driver pulley 54 which rotates a shaft 56 in which the pulley 54 is mounted. The shaft 56 will drive a lower shaft 58 through a gear connection as at 60 which results in the positive rotation of pairs of upper and lower driving pulleys 62 that power pairs of upper and lower endless timing belts 64 connected between the driving pulleys 62 and driven pulleys 66 connected on either end of shafts 68.

Endless belts 64 are disposed in upper and lower driving pairs disposed parallel to the line of feed 28 and spaced apart so as to frictionally engage successive pieces 20 adjacent the ends thereof on either sides of the continuous tape 18. Operation of the electric motor 34 causes the taped pieces 20 to move along the line of feed 28 at a constant rate of speed resulting in the tape 18 likewise moving at a constant rate of speed. The pieces 20 and the tape 18 are made of a material which may be fed in this manner without tearing apart. Of course the spacing between successive pieces 20 can never exceed the effective feeding length of the endless belts 64 or the forward holding point of the tape 18 would disappear as it is pieces 20, before the edges thereof are trimmed, which maintain the position of the front end of the tape 18.,

By leaving the center space between the pairs of belts 64 open, ample room is provided for the sensing and cutting operations. The present invention makes it possible to trim the tape at each of the edges of the pieces with great accuracy whether the pieces are uniformly or randomly spaced from each other along the continuous tape. Each of the identical pieces 20 has a leading edge 70 and a trailing edge 72, and is stitched to the tape 18 spaced apart from each other. On operation of electric motor 34 endless belts 64 will feed the pieces 20 and the connected continuous tape 18 at a constant rate of speed to the sensing mechanism 14.

The sensing mechanism 14 includes a trailing edge sensor 74, and a leading edge sensor 76 positioned in proximity to and forwardly of the trailing edge sensor edge 74. Sensors 74 and 76 are offset from the line of feed 28 and through coaction enable the tape to be cut from the edges of the piece; each sensor will operate independently of the other.

Sensor 74 employs a pair of pneumatic tubes, an upper tube 78 and a lower tube 80, extending from a controller 82. The controller 82 receives pressure air through line 84 from a suitable source, and discharges the pressure air through the line 78 at 4 p.s.i. and line at 2 p.s.i. The outlet of line 78 is in superposition to the outlet of line 80 and together the outlets define a trailing edge sensing point.

The outlet end line 78 is positioned above a chopping block 86, and the outlet end of line 80 is connected into block 86 with the respective outlets thereof in free communication with each other. The continuous tape 18 is drawn over the block 86 by the successive pieces 20, and of course are offset from the tape 18. Block 86 receives the impact below of the cutting device 16 and also serves to support the tape 18 prior to its being cut.

Individual cutting devices 16 are operatively connected to the sensor 74 and 76 to be individually triggered by said sensors. Each of the cutting devices 16 includes a pneumatic cylinder 88 the upper end of which is connected to the respective controller of the sensor 74 or 76 by a line 90. The lower end of cylinder 88 has a shaft 92 extending outwardly thereof from an internal piston connection (not shown). A knife 94 has a blade 96 formed along the lower edge and has the upper edge connected to the shaft 92. The blade 96 is disposed perpendicular to the line of feed 28 above block 86, and is of slightly greater length than the width of tape 18 so as to overlap the same on cutting thereof.

Accordingly the cutting device 16 associated With the sensor 74 is mounted in superposition to the line of feed 28 and the tape 18. The distance along the line of feed 28 from the sensing point of the tubes 78 and 80 to the longitudinal line of blade 96 is predetermined and for a given pattern or pieces 20 will be fixed distance. The distance will be established for a given system either empirically or otherwise by exactly matching the response time from the sensing to cutting and the anticipated distance the piece 20 will travel within such time. Regardless of how the distance is set the result will be to accurately cut the tape 18 exactly at the edge of the piece 20.

Controller 82 constantly discharges low pressure air from line 78 and senses the differential pressure evidenced by line 80. If nothing blocks the flow controller 8-2 remains inoperative. The controller 82 is set to permit the successive pieces to cover the outlet of line 80 and still remain inoperative, but on the trailing edge 72 passing to uncover the outlet of tube 80 controller 82 will immediately respond by sending pressure air at 90 p.s.i. through line 90 to operate the pneumatic cylinder 88 in a timed sequence that causes the blade 96 to slam down against block 86, thus severing the tape 18 accurately at the trailing edge 72. The pneumatic cylinder 88 may be spring or pneumatically unloaded and returned to its inoperative position after each actuation thereof.

The leading edge sensor 76 has pressure air delivered in line 98 from a suitable source (not shown) to a controller 100 wherein on receipt of a pre-set signal to be described hereinafter will send pressure air at 90 p.s.i. to the pneumatic cylinder 88 to cause the impact cutting of the tape 18. Controller 100 has a line 102 which discharges low pressure air at 4 p.s.i. from an outlet in superposition to the outlet of a second line 104 from which low pressure air at 2 p.s.i. is discharged. The superpositioned outlets of lines 102 and 104 define a leading edge sensing point and like the trailing edge sensing point will be positioned above and within, respectively, the block 86, offset from the tape 18 and the line of feed 28. The controller is set to remain dormant until the leading edge 70 covers the sensing point and then will immediately trigger the cutting operation of pneumatic cylinder 88 in a timed sequence to cause the knife 96 to sever the tape 18 at the just sensed leading edge 70 of piece 20. Once again the distance along the line of feed 28 from the leading edge sensing point to the blade 96 is fixed so as to effect the accurate cutting of the tape 18 exactly at the leading edge 70. Thus the sensing mechanism 14 by the individual operation of the sensors 74 and 76, and the cutting devices 16 combine to trim the tape 18 at the leading and trailing edges 70 and 72 respectively of the successive pieces 20, exemplified by the left most piece 20 as viewed in FIGURE 1.

The trailing edge sensor 74, the leading edge sensor 76 and the associated cutting devices 16 are positioned in operative pairs proximate to each other in which the distance between adjacent blades 96, 96 may be less than the stitched distance of the piece 20 along the tape 18. Thus for each successive piece 20 the leading edge 70 would be sensed at the leading edge sensing point to actuate the associated cutting devices 16 prior to the trailing edge 72 reaching the trailing edge sensing point. The result wouldbe that the tape 18 will be cut at the leading edge 70 prior to the tape 18 being cut at the trailing edge 72. This would provide a convenience on shutoff of electric motor 34 in that it would make possible a built in delay timed to permit the completed cutting operation of the leading edge 70 and the trailing edge 72 of a given piece 20. One way to accomplish this would be to interconnect the controller 82 in the circuit of motor 34 with means to prevent shutoff of the feeding assembly 12 on the trailing edge sensing point being covered for a sufficient period to permit the tape 18 at the trailing edge 72 to be cut. In other words the reservoir of stored pieces 20 will be sufiicient to permit the completed cutting operation of a piece 20 once it has been sensed by the sensing mechanism 14.

The timed sequence of operation of the cutting device 16 by the sensing mechanism 14 will vary according to the shape of the pieces 20 so that the fixed distance which was established for the edges of one particular piece may require adjustment if the edges of dilferently shaped pieces are to be trimmed. This adjustment may be readily made by moving either of the sensing points or the blades relative to each other.

Even though the knives 96, 96 which cut the tape 18 at the leading edge 70 and trailing edge 72 respectively, are spaced from each other at a distance less than the length of piece 20 along tape 18, each knife will operate separately of the other responsive to being individually triggered by the sensing means '74 and '76. Thus it is apparent that even if the spacing between knives 96, 96 were substantially increased this distance would not be critical. The accuracy of the cutting of the tape at the leading edge 70 and the trailing edge 72 is wholly dependent upon spacing the knife from the respective sensing points of sensors 74 and 76. If after operation of the edge trimming device 10 the tape is not out exactly at either leading edge 70 or trailing edge 72 the distance along the line of feed 28 between the knife 96 and its respective sensor would be adjusted to make it greater or smaller merely by moving one relative to the other. In this way a fixed distance between the knife and sensor would be established separately; for the leading edge 70 and the trailing edge 72. Proper adjustment of respective cutting and sensing positions would result in an exact and accurate cutting of the tape 18 at the edge in question.

Once the piece 20 has had the tape 18 severed at edges 70 and 72 it will be suitably collected at the discharge end of belts 64.

An. embodiment of the sensing and cutting means illustrated in FIGURE 2 provides for adjusting the distance along the line of feed 28 therebetween. The feeding assembly (not shown) will deliver the tape 18 and stitched pieces 20 along a line of feed 28 as described hereinbefore.

The sensing mechanism 14a operates to sense the leading edge or trailing edge of piece 20 by suitably adjusting the controller to trigger actuation of cutting device 16a in a timed sequence upon the sensing of the respective edge. The pneumatic cylinder 8811 includes a slotted mounting hole 112 which will permit limited adjustment along the line of feed 28 on mounting the cylinder 88a to the frame (not shown). The controller 110 receives pressure air from a suitable source in line 114 to deliver low pressure air in lines 116 and 118, with the upper line at a slightly greater pressure, to a segmented selector valve 120 having an upper disc 122 and a lower disc 124 operatively connected by a shaft 126 which permits the two discs to be turned simultaneously by a knob 128. The side of the discs 122 and 124 adjacent to the line of feed 28 has an upper manifold of tubes 130 and a lower manifold of tubes 132 each lettered a through e. The ends of the upper manifold of tubes 132 terminate in a plate 131 disposed above a similar end plate 133 of the lower manifold of tubes 132 so as to place each of the corresponding pairs of tubes a -a through e-e in superposition. An internal connection (not shown) in discs 122 and 124 will connect line 116 and line 118 respectively with one pair of lettered tubes from manifolds 130 and 132. Knob 128 includes an indicator 134 which indicates which pair of tubes is connected to the controller 110 through the selector valve 120. The numbered indicia on the selector valve 120. The numbered indicia on the selector valve indicates that the tubes aa corresponding to the number 1 is at the furthest distance along the line of feed 28 from a knife 94a, and that tubes e-e corresponding to the number 5 will be at the shortest distance along the line of feed 28 from the knife 94a. Though the distance between the pairs of tubes represented by the numbers 1 through 5 is shown quite large in practice it may be as close as so that it is possible to make minute distance adjustments to insure accurate cutting of the tape at the sensed edge of piece 20 by merely turning the knob 128 to connect one of the pairs of tubes a through e to act as the sensing point. Only a single tube from manifolds 130 and 132 will deliver pressure air and the remaining tubes will be dormant. The connected pair of tubes will operate in the same manner described hereinbefore whereby the respective edge of the piece 20 will be sensed to signal the controller 110 to actuate cutting device 16a. In the FIGURE 2 embodiment the sensing point is positioned to the right of the block 86a along the line of feed 28 but the respective tube ends are formed in a line 1 through 5 (see lower plate 133) disposed offset from the tape 18 and parallel to the line of feed 28.

FIGURE 3 illustrates another embodiment of the sensing mechanism, designated generally as 14b and the cutting device 16b both of which will operate in substantially the same manner as described hereinbefore. Accordingly, the controller 140 will receive a pre-selected sensing signal on tubes 142 and 144 detecting the respective edge of a piece 20 (not shown) as it passes along the line of feed, and thereafter actuate cutting device 1611 to cause the tape to be severed at the sensed edge of the piece. In order to match the response time of the sensing and cutting operations with the distance traveled by the piece after it has been sensed but before it has been cut adjustment means are provided. An adjustment may be made at a slotted connection of the pneumatic cylinder 88b to the frame (not shown), but it will probably be more convenient to adjust the relative location of the sensing point along the line of feed. Of course the distance between the sensing point and the knife blade 96b will require adjustment whenever the particular pattern of the piece to be trimmed is changed.

Block 86b has an impact zone 146 at the end immediately below the blade 96b there is a recess 148 along one edge into which is slideably fitted a slide block 150 having the tube 144 connected therein. Block 150 is adjustably positioned by a screw 152 engaged in a counter-bored slot 154 disposed parallel to the line of feed.

The screw 152 will be threadedly connected into block 8611 with the head thereof disposed slightly below the upper surface of block 150 so as not to interfere with the movement of the taped pieces. The sensing point of tubes 142 and 144 will be offset from the line of feed sufficiently so as not to be covered by the continuous tape 18 in order that it may sense the respective edge of the successive pieces in the manner described hereinbefore. The upper tube 142 which is fixedly connected in a slide bracket 156 which may be coupled (not shown) to block 150- or as shown in FIGURE 3 adjusted individually to a position which brings the outlets of lines 142 and 144 into alignment by a screw 158 disposed in a slot 160 that runs parallel to the line of feed 28. The screw 158 is threadedly received in a fixed bracket 162 that will extend from the frame (not shown). The slide bracket 156 has a recess 164 in which it slidingly engages the fixed bracket 162, thus permitting the tube 142 to be adjusted in superposition to the tube 144 so as to define the sensing point as described hereinbefore.

It will be understood that various changes in the details, materials, arrangements of parts and operating conditions which have been herein described and illustrated in order to explain the nature of this invention may be made by those skilled in the art within the principles and scope of the invention.

Having thus set forth the nature of the invention, what is claimed herein is:

1. A trimming device for cutting a continuous tape at the leading edge and the trailing edge of pieces individually connected to the tape in spaced relationship to each other, said trimming device comprising:

(a) means for moving the pieces connected to the tape at a predetermined rate of speed along a prescribed line of feed,

(b) sensing means adjacent to the line of feed including a leading edge sensing means to sense the leading edge of the pieces and a trailing edge sensing means to sense the trailing edge of the pieces,

(c) cutting means adjacent the line of feed including a leading edge cutting means downstream of the leading edge sensing means by a preselected amount to cut the leading edge and a trailing edge cutting means downstream of the trailing ede sensin means by a preselected amount to cut the trailing edge, and

(d) the leading edge sensing means and cutting means and the trailing edge sensing means and cutting means are disposed in operatively spaced pairs along the line of feed to permit independent cutting of the leading and trailing edges of the successive pieces in a timed sequence actuated in response to the respective leading edge sensing means and trailing edge sensing means.

2. The combination claimed in claim 1 wherein each of the sensing means includes:

(a) a pneumatic sensor, and

(b) a controller means connected between the pneumatic sensor and the associated cutting means, and adapted to translate the signal of the pneumatic sensor on the respective leading or trailing edge being sensed to trigger actuation of the associated cutting means independently of the operation of the other sensing and cutting means.

3. The combination claimed in claim 1 wherein:

(a) the leading edge sensing means and cutting means is disposed along the line of feed forwardly of the trailing edge sensing means and cutting means,

(b) the leading edge sensing means and cutting means are separated from the trailing edge sensing means and cutting means by a predetermined distance to permit the leading edge of the successive pieces to be sensed and cut in a timed sequence before the trailing edge sensing means and cutting means senses and cuts the trailing edge thereof.

4. The combination claimed in claim 2 wherein:

(a) the leading edge sensing means is operative responsive to each successive piece covering the pneumatic sensor thereof to actuate the timed sequential operation of the leading edge cutting means that severs the tape a the leading edge of each successive piece,

(b) the trailing edge sensing means is operative responsive to each successive piece uncovering the pneumatic sensor thereof to actuate the timed sequential operation of the trailing edge cutting means that severs the tape at the trailing edge of each successive piece.

5. The combination claimed in claim 4 wherein:

(a) the leading edge sensing means and cutting means, and the trailing edge sensing means and cutting means are spaced in pairs along the line of feed at a distance from each other not to exceed the taped length of the pieces whereby the leading edge and the trailing edge of each successive piece will be sensed and cut within the distance traveled by each successive piece of less than its taped length.

6. In a trimming device for successively cutting spaced pieces adjacent the leading edge and the trailing edge thereof to sever the same from its connection to a continuous tape, a trimming assembly comprising:

(a) a pair of spaced feeding means disposed on either side of the tape to define an open area through which the tape passes,

(b) each of the feeding means to engage a plurality of pieces and to feed the pieces at a constant rate of speed along a prescribed path through the open area,

(c) a pair of sensing means including a leading edge sensor and a trailing edge sensor, each of the sensors is disposed in the open area,

(d) a pair of cutting means including a leading edge cutter and a trailing edge cutter, each of the cutters is disposed in the open area, and

(e) the leading edge sensor and cutter, and the trailing edge sensor and cutter are disposed in operatively spaced pairs within the open area independently to sense and to cut the leading edge and the trailing edge respectively of successive pieces from the continuous tape as the tape passes through the open area.

7. The combination claimed in claim 6 wherein:

(a) the sensor is pneumatically operable,

(b) the pneumatic sensor includes a plurality of tube means disposed parallel to the line of feed with each tube located at the different distance from the cutting means,

(c) a selector valve connected to the manifold to selectively activate one of the tube means of the manifold at a predetermined distance from the cutting means to act as the pneumatic sensor and deactivate all the other tube means of the manifold.

8. The combination claimed in claim 6 wherein:

(a) means are intermittently operable to stop the feeding means in response to an inadequate reservoir of taped pieces being available for feeding at the predetermined rate of speed, and to start automatically the feeding means on build up of said reservoir.

References Cited UNITED STATES PATENTS 4/ 1956 Klauss et a1. 8/1964 Donnell 832ll 2/1965 Hofiman et a1 83-365 X 4/ 1965 McCormick et a1 83364 US. Cl. X.R. 

